Project Statement

Today, as our constantly-fluctuating climate causes rising sea levels, storm surges, and unexpectedly heavy rainfall, low-lying cities across the globe are bracing for urban flooding disaster. As sea levels rise and concrete infrastructure multiplies, Bangkok is sinking two centimeters every year.

For the first time in 30 years of rapid urban development, an invaluable property at the heart of Bangkok—11 acres of land and 1.3 kilometers of the road— was not turned into another block for commercial use. Instead, it is transformed into a public park for people. Opened in 2017, Chulalongkorn Centenary Park is the first critical piece of green infrastructure in Bangkok to mitigate detrimental ecological issues and reduce disaster risk. Unlike other public parks around the city, this is the first in Thailand to demonstrate how a park can help the city reduces urban flooding and confronts climate change, all while offering city dwellers a place to reconnect with nature. Designed with innovative ecological design components, the park reminds the city how to live with water, rather than fear it.

Project Narrative

Sinking cities: our new normal

Sitting on the floodplains of the Chao Phraya River, Bangkok has always lived with water in an interdependent amphibious relationship. Today, urban sprawl has gone unchecked, underground water is used excessively, and weight from high-rise buildings is increasing rapidly. Explosive development ignores the city's delta landscape and its porosity while eating away natural waterways and agricultural land that once absorbed water. The entire city can be flooded within just 30 minutes of rainfall: by 2030, it could submerge many major areas in the city and surrounding areas. Bangkok is a capital city with one of the lowest ratios of public green space of just 3 Sq.m, compared to the average of 9 Sq.m per person. The city is now facing an inevitable reality of climate change.

A green model for Bangkok's future

For the first time in 30 years, a priceless plot at the center of Bangkok's commercial district—11 acres of land with a 1.3-kilometer stretch of road worth US$700 million—was not turned into a shopping mall or office building. Instead, it was transformed into a public park. For its 100th anniversary, Thailand's very first university, Chulalongkorn University, wanted to give back to society by offering property extending from its core campus for a new public park as part of a 2012 design competition.

As climate change exacerbates both drought and extreme rainfall in the city and in the years to come, the design team posed questions envisioning challenges of the future: What will Bangkok confront 100 years from now? How can this park carry on the university's legacy and role as a pioneer in Thailand, as has been the case over the past century?

The designer concluded that this park's vision could not be merely beautification or recreation. The team realized that Bangkok needs not only more green space but more resilient landscaping to tackle climate change and its water challenges.

After five years of numerous meetings, building upon a community-oriented design process with committees, students and surrounding stakeholders, the designers were able to develop an activity program for the park, while ensuring its purpose in mitigating urban climate change. Fulfilling both the social and environmental impacts it needed to address, the Chulalongkorn Centenary Park was launched in 2017.

A flood-proof park for a flood-prone city

Bangkok is a flat city. By harnessing the power of gravity, The park is able to sustainably collect, treat, and hold water to reduce urban flood risks in its surrounding areas. Sitting on a three-degree angle,the park is equipped with several ecological features, from its highest point,—green roof, wetlands, detention lawns, to its lowest point, retention pond—leaving not a single drop of rain wasted. The rain and runoff are pulled down through the park's topography to generate a complete water circulation system. Taking into account a 50-year period of rainfall intensity and the frequently overwhelmed public sewage system, the park is able to hold up to a million gallons of water during heavy rainfall.

At the park's highest point, any member of the public can see Bangkok's skyline—not on an expensive rooftop bar or a skyscraper helipad, but atop the biggest green roof in Thailand covering 5,200 square meters where open skies and green grass are free to all. Laid with low-maintenance native grass and weeds which attract local birds and insects, the roof provides a unique experience of a rural and natural environment with a dense urban backdrop.

Underneath the green roof lies a museum and parking space, made possible by the inclined architecture. Additionally, three underground tanks store rainwater absorbed from the green roof. The amount of water held can irrigate the park for up to a month during dry seasons.

Excessive runoff from the green roof then flows down to four constructed wetlands, two on each side of the park. A series of cascading weirs and ponds slow the runoff and increase water aeration, aided by native water plants that filter and clean the water. In the concrete city of Bangkok, the park provides a hidden oasis where kids and adults can explore and interact with wetlands and hear the sound of flowing water.

The main lawn at the park's center is a vast inclined open space for recreational activities. Unlike other flat parks around the city, this inclined park offers the unique experience of multi-purpose amphitheater for public events. On stormy days, the lawn absorbs rain and runoff, using gravity to send the water to the retention pond by the low end of the park. During severe flooding, this retention pond can store excessive water and double in size by expanding into the park's main lawn. Visitors, too, can become an active part of the park's water treatment system by hopping onto any stationary water bikes along the pond and using their exercise to keep the water aerated.

Featuring sustainable drainage systems, a green roof, wetlands, porous areas, ponds, an open swale, small pocket parks, detention lawns, and a retention pond, the park is a premiere example of various landscape solutions for urban flood disaster reduction. Bangkok desperately needs more parks, but more importantly, productive ones that can sustainably confront climate uncertainty. By demonstrating the potential of landscape architecture, Chulalongkorn Centenary Park shows the city ways to live with water, rather than fear it.

While playing a role in confronting climate risk, the park simultaneously serves as a recreational space and outdoor classroom for the university community, surrounding neighborhoods and urban dwellers. Adjacent to the main lawn are eight "landscape outdoor classrooms," each with different biomes and layouts,lining both sides of the park to serve as diverse multi-purpose areas. They include an herb garden, meditation area, reading room, bamboo garden, playgrounds, and earthen amphitheater. Whether in the choice of porous components or locally-sourced materials, these outdoor classrooms incorporate details to best complement the park's main ecological features.

As Bangkok experiences droughts and monsoons, the park's water and landscape will continually grow and transform to unveil new environments for visitors to experience. Following the planting concept of establishing urban forests, 258 varieties of plants and trees have been grown either from seed or as young seedlings which easily adapt to climate changes, recreate a healthy ecosystem, and provide habitat for local birds, pollinators, and insects.

The first green avenue made for the people

The first of its kind in Bangkok, the 1.3-kilometer road running perpendicular to the park was redesigned to shift priority from cars to pedestrians and cyclists. By reducing four vehicle lanes into two, providing space for people walking and biking, the once heavily-congested street now seamlessly connects pedestrians and cyclists directly to surrounding neighborhoods' residential, entertainment, and retail facilities. The park is lined with corridors of rain gardens on both sides to provide shade and human comfort, and reduce runoff from the adjacent road surface. This design is evidence to Bangkok the possibility of a commercially-developed area that is, finally, pedestrian-friendly.

While climate change has been a prominent issue for decades, we are undoubtedly moving towards an age of sustainability and resiliency. A single park cannot control flooding across an entire city, but Chulalongkorn Centenary Park is a big, bold first step. Urban development is inevitable and the population is bound to rise, but it is our obligation as landscape architects to consider every possible solution and sign of hope for our future. The Chulalongkorn Centenary Park gives Bangkok a spark of aspiration in how the city can choose to address its threatened future while allowing new landscape architecture strategies to emerge.